Which is a common sign of equipment wear and tear?

Unusual noises are a common sign of equipment wear and tear because they often indicate that mechanical components are not functioning as they should. As equipment ages and experiences normal wear from usage, parts may become loose, damaged, or misaligned, leading to sounds that are atypical of normal operation. For instance, grinding, squeaking, or rattling noises can suggest that bearings might be failing, gears are not meshing correctly, or there is some friction occurring where it shouldn't be.

In contrast, brightly colored paint is more a matter of aesthetics or branding rather than an indicator of wear. Increased fuel economy would generally suggest that equipment is functioning efficiently, which contradicts the concept of wear and tear, as deteriorated components typically lead to less efficiency. Consistent performance also implies that equipment is running well and is unlikely to show signs of wear; worn equipment is more likely to exhibit fluctuations and decreased reliability in performance.